1. Field of the Invention
The present invention relates to a digital video disc playback system, and more particularly, to a sync data restoring apparatus and method which are capable of accurately restoring data recorded on a digital video disc (DVD) despite damaged sync data in a digital video disc playback system.
2. Description of the Related Art
The basic technology of the optical disc for reading data in a non-contact manner using a laser light has been greatly developed since its establishment about 20 years ago. As a result, current compact discs (hereinbelow, referred to as CD) having a one side disc structure of a diameter of 120 mm and a thickness of 1.2 mm are widely used. It is possible to record data of approximately 640 Mbytes on one side of such a CD. However, in the technical field of optical discs, as the rotating speed, overwriting and density (increased storage capacity) have increased due to the development of a short-wavelength laser or recording playback technology, a storage medium, for example, a Digital Video Disc (hereinbelow, referred to as DVD) has recently been introduced. The DVD and the CD share the one side disc structure having a diameter of 120 mm and a thickness of 1.2 mm. However, the DVD can record much more data (about 6 times; data of 4.7 GByte) compared to the CD. Accordingly, the DVD is a recording medium suitable for an optical system for the next generation in which an increase in the amount of information will be required.
DVD related technologies have required a record and reproduction of high density. If a small glitch is generated or an error of sync data during reproduction, it may be impossible to accurately reproduce the data. Further, technology which enables accurate reproduction of data recorded on a disc despite damaged sync data is required.